shore banks or shoals or along channels during 

 the spring and fall migrations. Nets for round- 

 fish and flatfish are readily interchangeable, 

 and often the same vessel will fish both nets, 

 in the shallow waters along the coast, during a 

 single day's operations. 



The offshore trawl fleet fishes over a 

 wide range of depths and localities. Fishing 

 normally begins somewhere between the 10 and 

 15 fathom lines in early October and gradually 

 moves farther offshore until much of the trawl- 

 ing in February and March is done along the 

 edge of the continental shelf. The grounds 

 fished during the 1952-1953 season are shown 

 in figure 9. Fishing occurs throughout the en- 

 tire area. Grounds of greatest importance to 

 the fishery lie 30 to 60 miles southeast of Dela- 

 ware Bay, roughly defined by a circular area 

 of approximately 1,500 square miles. Over 50 

 percent of the fishing effort was spent on these 

 grounds in 1952-1953. 



Catch 



During the 8 -year period, 1946 through 

 1953, the average annual production of the otter 

 trawl fishery within the survey area was 176 

 million pounds (fig. 10). Following an initial 

 peak in 1947, the catch declined steadily through 

 1951 . A catch of over 20 million pounds was 

 recorded in 1953. The trend of offshore trawl 

 production has been upward, while the inshore 

 trawl yield has declined somewhat over the 8- 

 year period. 



Inspection of tables 3 and 4, which list 

 species composition for the inshore and off- 

 shore fleets respectively, shows that fluke, 

 porgy, and weakfish accounted for nearly 75 

 percent of the inshore landings, and porgy, sea 

 bass, and fluke comprised 86 percent of the 

 offshore catch during the period considered. 

 From table 3 it may be seen that whiting was 

 the most important species in 1946 and 1947. 

 It contributed little to the catch in subsequent 

 years. Fluke has become of increasing im- 

 portance and comprised over one -half the total 

 catch in 1953 . In the offshore trawl fishery, 

 percentage contribution of the three principal 

 species has fluctuated within rather narrow 

 limits, with the possible exception of sea bass 

 (table 4). Porgy has, almost consistently, led 



other species. Composition of the "all others' 

 category varies somewhat from season to season. 

 However, changes between seasons usually are 

 less than one percent of the annual landings. 

 Table 5 lists the miscellaneous species contribut- 

 ing to the inshore and offshore catches. 



The inshore otter trawl fleet operates 

 during the entire year, although fishing during 

 the winter months is somewhat sporadic due to 

 unfavorable weather conditions. The fish, gen- 

 erally, are less abundant on the inshore grounds 

 during this period. The first appearance of the 

 fish, marking the commencement of the summer 

 fishery, usually occurs in May. Figure 11 shows 

 the season of peak production with average monthr 

 ly catches expressed as percentages of the aver- 

 age annual catch for the 8 -year period, 1946 

 through 1953 . About 86 percent of the landings 

 are made in the period May through November. 

 It should be noted that the fishery for whiting and 

 red hake in 1946 and 1947 was pursued most in- 

 tensively in April and May. 



The offshore trawl fleet also fishes 

 throughout the year . Over 90 percent of the 

 landings, however, are made from October 

 through May. Figure 12 shows the average 

 monthly percentage of the annual catches for the 

 period 1946 through 1953 . 



Compilation and Analysis of Data 



Methods of calculating apparent abundance 

 of food fishes in the trawl fishery were essential- 

 ly the same as for the menhaden fishery. Be- 

 cause of differences in season of operation, 

 fishing grounds, vessel efficiency, and, to a 

 certain extent, species composition, between 

 the inshore and offshore fleets, a separate series 

 of indices was calculated for each. 



To eliminate those scattered landings 

 which preceded and followed the period during 

 which the bulk of the catches were made, the 

 following seasonal periods were chosen for the 

 analyses: 



1 . Inshore fleet - May through October 



2 . Offshore fleet - October through June . 



Criteria for selection of vessels used 

 in the analyses were generally the same for both 



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